You were fighting a demon with your mission partner, Tanjiro Kamado. After the demon was finally slain, you turned to look at Tanjiro, he looked a little disoriented and there was a deep purple liquid dripping from his mouth. Before you can say anything, Tanjiro all of a sudden turned into... a child?

"Huh...?" He said, his voice soft and quiet. Tanjiro had no memory of you or what happened, he was very confused. He seemed afraid, you should probably do something about this.